Citric Acid → 3-Methyl-4-nitro-1H-pyrazole-1-ethanol

HRID 1045969Notes

Reaction equation

HRID 1045969 reaction equation
[CH3:1][C:2]1[C:6]([N+:7]([O-:9])=[O:8])=[CH:5][N:4]([CH2:10][C:11](OCC)=[O:12])[N:3]=1.[H-].C([Al+]CC(C)C)C(C)C.C(O)(=O)CC(CC(O)=O)(C(O)=O)O>C1COCC1>[CH3:1][C:2]1[C:6]([N+:7]([O-:9])=[O:8])=[CH:5][N:4]([CH2:10][CH2:11][OH:12])[N:3]=1

Participants

5

Reactant 3

HCID 311Citric AcidHCID 21225700DiisobutylaluminumhydrideHCID 67075924HCID 67075924, compound

Product 1

HCID 670760523-Methyl-4-nitro-1H-pyrazole-1-ethanolYield 91%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a stirred solution of the ethyl 2-(3-methyl-4-nitropyrazol-1-yl)acetate (0.69 g, 3.24 mmol) in THF (24 mL) at −20° C. under N2 was added diisobutylaluminum hydride (1M in toluene, 6.5 mL) over 5 min. maintaining the temperature below −20° C. The solution was allowed to warm to room temperature overnight. The reaction mixture was poured into sat. aq. citric acid (60 mL). The phases were separated and the aqueous phase extracted with EtOAc (4×30 mL). The combined organic phase was washed with sat. aq. sodium potassium L-tartrate (3×20 mL) and brine (30 mL), dried (MgSO4) and the solvent removed to give 2-(3-methyl-4-nitropyrazol-1-yl)ethanol as a pale yellow oil (0.50 g, 91%). Mass spectrum: MH+ 172

Workup

  1. temperaturemaintaining the temperature below −20° C
  2. customThe phases were separated
  3. extractionthe aqueous phase extracted with EtOAc (4×30 mL)
  4. washThe combined organic phase was washed with sat. aq. sodium potassium L-tartrate (3×20 mL) and brine (30 mL)
  5. dry with materialdried (MgSO4)
  6. customthe solvent removed

Sources & evidence

ORD record
ord-7b90b4f06a8141ca93f9ae6aa6bce256
Source dataset
uspto-grants-2013_10
Patent number
US08569298B2

Reaction notes

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